Question

所以我有一个mysql数据库可以使用这个触发器

delimiter $$
create trigger update_memberID
after update on memberdata  
for each row
Begin
if not (new.visits <=> old.visits) then
  insert into membervisit (memberID) values (new.memberID);
  end if;
if not (new.memberID <=> old.memberID) then
 update membervisit set memberID = new.memberID where memberID =     old.memberID;
  end if;
end$$
delimiter ;

现在我正在尝试在SQLite上设置相同的数据库，但是这个触发器正在运行。我对SQLite触发器的代码是

"CREATE TRIGGER IF NOT EXISTS `membership.update_memberID` " +
" AFTER UPDATE " +  
" ON memberdata " +
" FOR EACH ROW BEGIN " +       
" SELECT CASE WHEN (new.visits <= old.visits) THEN " +
    " INSERT INTO 'membership.membervisit' ('memberID') values (new.memberID);" +
            "END;\n" +

" SELECT CASE WHEN (new.memberID <= old.memberID) THEN " +
    "UPDATE `membership.membervisit` SET `memberID` = `new.memberID` WHERE `memberID` =`old.memberID`;" +
            "END;" +
"END;"

我收到的错误是

Exception in thread "main" java.sql.SQLException: near "INSERT": syntax error
    at org.sqlite.core.NativeDB.throwex(NativeDB.java:397)
    at org.sqlite.core.NativeDB._exec(Native Method)
    at org.sqlite.jdbc3.JDBC3Statement.executeUpdate(JDBC3Statement.java:116)
    at SQLiteSetup.main(SQLiteSetup.java:62)
C:\Users\Owner\AppData\Local\NetBeans\Cache\8.1\executor-snippets\run.xml:53: Java returned: 1
BUILD FAILED (total time: 0 seconds)

它引用的插入是

" INSERT INTO 'membership.membervisit' ('memberID') values (new.memberID);"

任何帮助将不胜感激感谢

Answer 1

CASE是一个表达;你不能用它来表达。

但在SQLite中，触发器可以有WHEN clause。（在SQLite中，NULL安全比较是IS。）

CREATE TRIGGER update_memberID_visits
AFTER UPDATE OF visits ON memberdata
FOR EACH ROW
WHEN NEW.visits IS NOT OLD.visits
BEGIN
    INSERT INTO membervisit(memberID)
    VALUES (NEW.memberID);
END;

CREATE TRIGGER update_memberID_memberID
AFTER UPDATE OF memberID ON memberdata
FOR EACH ROW
WHEN NEW.memberID IS NOT OLD.memberID
BEGIN
    UPDATE membervisit
    SET memberID = NEW.memberID
    WHERE memberID = OLD.memberID;
END;

SQLite触发器插入错误

1 个答案: